Fasteners have been designed in many shapes, sizes, and configurations for joining two or more objects together. Screws and bolts are some of the more commonly used fasteners for joining objects. Most screws and bolts fall under the category of externally threaded fasteners which include external threads (e.g., male threads) wrapped around a cylinder extending from a head of the fastener. Externally threaded fasteners may be designed for assembly with a nut or an object having a nut thread matching the thread of the fastener. Other externally threaded fasteners may have ends designed for insertion into a hole (e.g., a pre-drilled pilot hole, punched hole, or nested hole) or may have an end with a pierce-point that is designed to penetrate a surface of the object to be joined. A pierce point, also known as a needle point, speed point or sprint point, provides a sharp end point that is configured to pierce the surface to be joined.
A fastener with a pierce point may be used, for example, to join sheet metal to other objects. As the pierce point of the fastener pierces through the sheet metal, the thread of the fastener engages and drives the fastener through the layer(s) of the sheet metal and, if provided, into other object(s) with ease and great speed.
In applications where the fastener is exposed to elements (e.g., weather elements) that may corrode the fastener, the fastener is coated with a protective material layer (e.g., paint, zinc, or copper). Unfortunately, however, during the process of coating the fastener, the sharpness of the end point may be compromised due to deposits of the coating material on the end point. In addition, during the process of coating the fastener, due to processes involved in the coating, a heavier layer of material may be deposited on the polar ends of the fastener. While such heavier deposition of the material on the head end of fastener may not have an adverse effect, a thick coating on a pierce point rounds off what should be a sharp point. This rounding causes the pierce-point to be less effective in quickly piercing the surface to be fastened and in some cases may not even allow the surface to be pierced. Such rounding of the pierce-point is particularly observed during an electroplating process that causes a heavier layer of material (e.g., zinc) to be formed on the ends of the fastener than the center portion of the fastener including the threads.
Certain example embodiments address these and/or other concerns. For instance, certain example embodiments relate to a fastener with a point end geometry that is less affected by unequal distribution of a coating material. Certain example embodiments provide a fastener with a self-drilling point that allows for quick fastener installation. The geometry of the self-drilling point reduces the undesired buildup of coating material on the end of the fastener.
In certain example embodiments, a fastener may include an elongated shank, a head at a distal end of the shank, and a drill point at a terminal end of the shank, which is opposite to the distal end. The fastener may include a primary thread starting at the drill point and extending along the shank towards the head. The fastener may include a secondary thread starting at the drill point, extending along the shank towards the head, and stopping in an axial direction before the primary thread ends. The secondary thread may be radially located 180 degrees from the primary thread. The drill point may include a plurality of radially extending cutting edges and one or more relieved flute portions extending along the surface of the drill point.